Monday, April 2, 2007

Issue 17: Do Environmental Hormone Mimics Pose a Health Threat?

Issue 17

Do Environmental Hormone Mimics Pose a Potentially Serious Health Threat?

Authors: Michele L. Trankina and Michael Gough

1. (2pts) Definitions. List the important new terms and concepts used by the author. Define terms with which you were not familiar. Circle those that you think need clarification and discussion. Minimum 4.

a. junk science versus bad science (according to Mr. Gough) – junk science is science that is based off of ideology; bad science is science with honest mistakes. It’s the intent behind it that distinguishes a difference.

b. endocrine disruptor – a chemical that can disrupt, alter, or increase a normal physiological function in the body.

c. environmental estrogens – “many synthetic compounds and plant products present in the environment [that] have been found to affect hormonal functions in various ways.” (p. 304)

d. estrogen mimics – disruptors that bind to estrogen receptors on the membranes of cells that cause changes in reproduction and growth.

2. (4pts) Summary. In your own words, summarize the themes and key points developed in this chapter, article, or section of an assigned book. Write as if you were the author telling another educated person what you were trying to say in the assigned piece. In this section, do not give your opinion. Present the arguments and themes of the assigned author.

Michele L. Trankina, a professor of biological sciences, provides the positive argument. She uses the alligator population in Lake Apopka, Florida, which was studied by Louis Guillette. He found that the population was decreasing, male genitalia were smaller, and that females super ovulated. He linked it to a spill in 1980 of DDT (dichloro-diphenly-trichloroethane). DDT, in this case, acted as an estrogen mimic that resulted in the feminization of the males and over-feminization of the females.

This lead to curiosity of other effects of DDT. In rodents, high exposure to the substance caused testicular cancer in males and mammary tumors in females. As DDT concentrations increase higher in the food chain, we are lead to wonder what effects chronic exposure it would hold for humans.

A 1993 article, published by two authors from Holland and Scotland, looked at the decreases in sperm counts of males in the United States and twenty other countries. The decrease correlates to the increase of concentrations of environmental estrogens.

It is thought that through accidental contamination of cattle with polychlorinated biphenyls (PCBs), women’s breast milk was highly concentrated with it. Their sons demonstrated defective genitalia – problems ranging from cryptorchidism (undescended testes) to hypospadia (urethra opening on the underside of the penis instead of the tip). More research is needed to a full correlation.

Precocious puberty, which is puberty before the ages of 12-13, is increasingly common in girls: 7% white and 27% black exhibiting pubertal growth by the age of seven. This might be from increased fat in the body; it might be from environmental factors. Most likely, it is a combination of both and deserves future study.

There is quite a bit of evidence that shows certain plastics have chemicals that can leach into our foods. It’s not just food either, Barbie dolls from the 1950’s and 1960’s have been found to release a stabilizing chemical from the PVC. The resulting residue is found to mimic estrogen. Many other things that are plastic surround us as well, too. How are we to know which is safe and which is not? These are all questions that, if concerned, we must research more and be aware of to protect ourselves. Fortunately, citizens are not alone in this; many organizations are committed to the cause of minimizing the effects of environmental estrogens as well.

Michael Gough, of the Cato Institute, provides the negative argument. He claims the science used to collaborate environmental estrogens to illnesses is faulty and that its environmentalist scare tactics that have caused billions of dollars wasted in research and testing products from plastics to pesticides.

He claims that the very existence of the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) is based off of faulty scientific evidence and scare tactics, namely, the carcinogenic agents found in our water supply, at our workplaces, and in our homes. By naming and regulating or removing these carcinogens, we could remove cancer from our lives. So bureaucracy believes they can remove cancer from our population. The EPA, in an effort to justify their existence, created list after list of carcinogens that we are exposed to. He claims that the Love Canal in New York, as it was blamed to be contaminated with carcinogenic wastes that caused “cancers, birth defects, miscarriages, skin diseases,” (p. 311) was all a hoax that has led to similar “Love Canal incidents” in every state. He says this only taxes the government’s resources with laws such as the Superfund Law to clean up what doesn’t need cleaning.

He believes that the decline of cancer rates in our nation is debunking the ‘cancer scare’. He argues that Dr. Theo Colborn, researching for cancer rates in the Great Lakes area and finding that they were decreased, “reached” in her exploration to find any collaboration between chemicals and an adverse effect on health.

She found endocrine disruptors, which she linked to abnormal responses from wildlife. She tried to collaborate this to humans, and found decreased sperm counts in males since World War II. Gough tries to make it out to seem as though Dr. Colborn was intending to find such results and therefore, found them.

He also scoffs the Tulane research and results. The Tulane paper connected the pesticides and other chemicals that can behave as estrogen disruptors to its presence in our food. This alarmed the EPA, Congress, the media, the scientific community, and the citizens. As a result, the Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) were created, along with the Food Quality Protection Act (FQPA). The EDSTAC is now considering tests for all 70,000 known chemicals that are present in our nation and are adding additional tests to screen for testosterone and thyroid hormone disruptors. The total cost of this is estimated to be between $5 and $10 billion. The FQPA requires tests on our food for pesticides and evaluates the acceptable level of them. The Tulane report was then never replicated, despite efforts from the original researcher, Dr. John McLachlan and others.

Regardless of the research failure, the FQPA will continue, and is expected to result in the removal of 50-80% of pesticides from the market. This cost will directly impact companies, who will in turn, pass it on to farmers. The farmers then will increase the price of their product and the poor will be less likely to purchase healthy food such as fruits and vegetables. Without eating right, health problems will increase in the poor and some middle class, and here the cycle continues.

3. (3pts) Creative Reaction and Integration. Record some of your own ideas that came to you as you were reading and thinking about the issue or issues the author is discussing. Formulate these in well-written sentences, develop them as best you can, and relate them to the author’s discussion and possibly to other readings and course themes.

Gough is an interesting character. He finds Dr. Colborn in the worst light – trying to bunk her science to reach a goal. This is a serious charge of fraudulent work in research.

It is convincing that plastics and pesticides could contaminate our water, food, and living space. It’s happened before and it mostly likely will happen again, or happening now. This is something we need to take seriously. The correlation between the chemicals found in our products, the effects these chemicals have in laboratory settings, and the statistical evidence of ever-growing health problems is too great to ignore.

4. (2pts) Opinion – Not graded, 2 points awarded if completed.

We should employ the precautionary principle here. The evidence, while circumstantial, is enough to build upon in research and in court. There is no need for us to wait until we are dying of cancer to have to prove to the court that this chemical was contaminating us.

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